Iterative Tuning of Power Electronic Controllers by Utilizing Weighted Hankel Singular Values and Eigenvalue Sensitivities

This paper presents an iterative algorithm for tuning of converter control loops by utilizing parametric eigenvalue sensitivities. The tuning algorithm is designed to affect the eigenvalues representing poorly damped oscillations or slow responses that significantly impact the system outputs. The critical eigenvalues to be addressed by the algorithm are identified by weighting their real part and their corresponding Hankel Singular Values (HSV). For this purpose, a simple procedure is proposed to associate each eigenvalue to an HSV. The functionality of the proposed algorithm is illustrated by a numerical example showing the tuning of a grid-connected voltage source converter with a grid-forming control strategy. The results show how the dynamic response of a system can be significantly improved by utilizing the proposed tuning algorithm for moving the location of the identified critical eigenvalues. Moreover, it is highlighted how identification of critical modes by considering both the real part of the eigenvalues and the corresponding HSV produces a more efficient and effective iterative tuning.